Preterm Neuroimaging and School-Age Cognitive Outcomes

Abstract

Background and objectives: Children born extremely preterm are at risk for cognitive difficulties and disability. The relative prognostic value of neonatal brain MRI and cranial ultrasound (CUS) for school-age outcomes remains unclear. Our objectives were to relate near-term conventional brain MRI and early and late CUS to cognitive impairment and disability at 6 to 7 years among children born extremely preterm and assess prognostic value.

Methods: A prospective study of adverse early and late CUS and near-term conventional MRI findings to predict outcomes at 6 to 7 years including a full-scale IQ (FSIQ) <70 and disability (FSIQ <70, moderate-to-severe cerebral palsy, or severe vision or hearing impairment) in a subgroup of Surfactant Positive Airway Pressure and Pulse Oximetry Randomized Trial enrollees. Stepwise logistic regression evaluated associations of neuroimaging with outcomes, adjusting for perinatal-neonatal factors.

Results: A total of 386 children had follow-up. In unadjusted analyses, severity of white matter abnormality and cerebellar lesions on MRI and adverse CUS findings were associated with outcomes. In full regression models, both adverse late CUS findings (odds ratio [OR] 27.9; 95% confidence interval [CI] 6.0-129) and significant cerebellar lesions on MRI (OR 2.71; 95% CI 1.1-6.7) remained associated with disability, but only adverse late CUS findings (OR 20.1; 95% CI 3.6-111) were associated with FSIQ <70. Predictive accuracy of stepwise models was not substantially improved with the addition of neuroimaging.

Conclusions: Severe but rare adverse late CUS findings were most strongly associated with cognitive impairment and disability at school age, and significant cerebellar lesions on MRI were associated with disability. Near-term conventional MRI did not substantively enhance prediction of severe early school-age outcomes.

FIGURE 1

Independent associations of neonatal neuroimaging findings with cognitive impairment and moderate-to-severe disability at early school age. A, FSIQ <70. B, Moderate-to-severe disability. Early CUS composite adverse finding was defined as grade III or IV ICH or cPVL. Late CUS composite adverse finding was defined as moderate or severe VE, cPVL, porencephalic cyst, or shunt. The full model included the following perinatal, neonatal, and sociodemographic factors that were associated with P < .2 in backward stepwise models: FSIQ <70: male sex (OR: 2.07; 95% CI 1.0–4.28; P = .049), maternal education less than high school (OR: 2.05; 95% CI 0.98–4.29; P = .056), BPD (OR: 1.59; 95% CI 0.78–3.23; P = .20); moderate-severe disability: male sex (OR: 1.93; 95% CI 0.98–3.80; P = .057), BPD (OR: 1.30; 95% CI 0.67–2.50; P = .44). Limited model 1 includes perinatal and neonatal factors, early CUS, and brain MRI (excludes late CUS); limited model 2 includes perinatal and neonatal factors, early CUS, and late CUS (excludes MRI). * P < .05; *** P < .001.